Brown azo dye.



extra STATES PATENT oFnm MYBTIL KAHN AN]; ANTON OSSENBECK, O

CORPORATION OF GERMANY.

r 'ELBERFELD, GERMANY, ASSIGNORSI'IO FARBENFABRIKEN VORM. ERIE-DR. BAYER & 00., or ELBEBFELD, GERMANY, A=

BROWN AZO 'DYE.

No Drawing.

Specification of Letters Patent. Application filed November 2, 1911. Serial No. 658,152.

Patented May 14, 1912.

obtained from one molecule of a tetrazo' compound of a diamin, such as benzidin, tolldin, para-phenylenedlamm and one molecule of a meta-phenylenediamin compound such as meta-phenylenediaminor metatoluylenediamin sulfonic acids. The new dyes are after being dried and pulverized dark powders yielding upon reduction with stannous chlorid and hydrochloric acid a diamin, triaminobenzene compounds and carbonic acid, dyeing cotton generally orange shades which on being diazotized and combined with meta-phenylenediamin turn into fast shades.

In order to illustrate the new process more fully the following example is given, the parts being by weight:.-'-18.4 parts of benzldin are tetrazotized in the known manner with 14 parts of nitrite and the tetraz'o compound is combined with a solution of 18 parts of meta-phenylenediamin suliionic acid. To complete the formation of the intermediate product soda is slowly added. to.

the mixture while itis being well stirred. The excess of soda is then neutralized and a solution of 17 .5'parts of the hydrochlorid of meta-diaminodiphenylurea is added and sodium acetate until the mixture reacts neutral to Congo-paper. It is stirred for several hours at ordinary temperature and afterward for the same time at C. care being liberated. The combination is complete, after the mixture has been'stirred for about one day. kaline and the dyestufl is salted out, filtered taken to neutralize the acid which is The solution .is then rendered aloil and dried. The dyestuif thus obtained having probably the following formula:

is after being dried and pulverized a dark brown powder which is soluble in water with a yellowish-brown coloration and in concentrated sulfuric acid with a blue coloration; yielding upon reduction with stannous chlorid and hydrochloric acid benzidin, 12.4-triaminobenzene-o-sulfonic acid, 1.2.4-triaminobenzene and carbonic acid. It dyes unmordanted cotton in orange shades which on being diazotized and combined with meta-'phenylenediamin turn into a yellowish-brown of good fastness.

meta-phenylenediam'in sulfonic acid the stead of meta-.diaminodiphenylurea metadiaminoditolylurea can be used.

We claim 1. The herein described new tetrakisazo dyestuffs, which are after being dried and pulverized dark powders duct-ion with stannous chorid and hydrochloric acid a di'amin, triaminobenzene com.- pounds and carbonic acid; dyeing generally orange shades which on being diazotized and combined with. meta-phenylenediamin turn into yellowish-brown shades of good fa'stness, substantially as described.-

Instead of benzidin other 'para-diamins, instead of the cotton ielding upon re- .2. The herein described new tetrakisazo dyestufi', which is after being-dried and pulverized a dark brown powder which is soluble in Water with a yellowish-brown coloration and in concentrated sulfuric acid with a blue coloration; yielding upon reduction with stannous chlorid and hydrochloric acid benzidin, 1.QA-triaminobenzene-5-su1- fonic acid, 1.2.4-triarninobenzene and carbonic a oid; dyeing cotton orange shades which on being diazotized and combined with meta-phenylenediamin turn into a yel- In testimony whereof we have hereunto set our hands in the presence of two subis scrlblng wltnesses.

MYRTIL KAHN. [1 s.] ANTON ()SSENBEOK. [L.s.'| Witnesses:

ALBERT N UFER, L. N UFER. 

